TRIPOLI- Since fleeing his southern Tripoli home seven months ago with his pregnant wife and daughter, Moataz Saleh al-Fagih has been staying for free in an apartment provided by his employer.

With rents in the centre of Libya's capital soaring as those displaced by fighting on its edge seek housing, the 35-year-old IT engineer says he has been unable to find anything he can afford.

"If I lose my job ... I will be homeless," Fagih said.

Since forces holding much of the eastern part of the country launched an offensive on Tripoli in early April, more than 120,000 people have been displaced, according to U.N. estimates.

A wide buffer zone was created behind the front lines, from which most residents were evacuated. Many flooded into the centre of the city of three million and have remained there as the offensive stalled. urn:newsml:reuters.com:*:nL8N27E00G

The cost of renting a furnished two-bedroom apartment has risen to about 3,000-4,000 Libyan dinars ($2,140-$2,855) per month from 1,500 dinars before April, said real estate broker Abdulmajid Ben Mansour.

Tenants are also being asked to pay six months rent as a deposit, usually in cash.

Though a liquidity crisis has eased slightly since last year, salary payments are often long delayed and it can still be hard to withdraw cash from banks, and Ben Mansour said some people are selling belongings including cars or jewellery to cover the advance.

Outside his office in the downtown Zawiyat al-Dahmani neighbourhood, dozens queuing to find a cheap apartment to rent were being turned away disappointed.

Housing supply through new construction has been limited by repeated bouts of fighting that have hit Tripoli since the NATO-backed uprising that toppled Muammar Gaddafi in 2011.

The purchase price for a two-bedroom apartment has more than tripled to 500,000 Libyan dinars since 2014, Ben Mansour said, with some of the rise also down to Libyans based abroad taking advantage of cheap black market dinars to invest.

Alongside those already displaced, some have sought housing in central Tripoli because of the fighting.

Sami Zayed Sobkha, a resident of the Mashroa al-Hadba area south of the centre in his 50s, said he wanted to move but could not afford more than 1,000 dinars. "There's more shelling on the area where I live, and I am trying to keep (my family) away from danger."

Fagih said the state should be capping rents, but the weakness of successive governments had prevented that.

($1 = 1.4015 Libyan dinars)

(Editing by Aidan Lewis and John Stonestreet) ((Aidan.Lewis@tr.com; +20-1001174410;))